Nanostructured Fe(III) catalysts for water oxidation assembled with the aid of organic acid salt electrolytes

Abstract We describe the preparation of three partially ordered iron-based catalyst films (Fe-OAc, Fe-Pro, Fe-But) with nanoporous structure by electrodeposition from organate electrolytes containing Fe2+. The anions of the organic acids assisted the partial ordering of the nanostructured Fe(III) catalysts for water oxidation. A model involving an electrical double layer is invoked to explain the role of the organate electrolyte system in their formation. Analytical results have revealed the main component of the iron-based films to be a β-FeOOH structure. The Fe-But catalyst catalyzed water oxidation in 0.1 m potassium carbonate solution with an average activity of 1.48 mA cm−2 and an overpotential of 433 mV.